Firefox, Seamonkey, Flock, Songbird and Netscape users canopen page source as DOM document, read faqopen CSS and JS files present on pageopen images using your preferred image viewer (e.g. GIMP or ACDSee)open PDF links with Acrobat Reader or Foxit Reader or what you preferedit textboxes content with your preferred editor and automatically see modified text on browser when you re-switch focus on it